Since about 3 or so days ago on the website, actually comes into effect on Sept 1st. When I was checking out flights to WA about a week ago it was the old policy (sporting goods account towards 5kg of you're checked baggage regardless of weight). Booked flights today and it's totally changed this is now the policy;
Guidelines for Guests who purchase their fare on or after 18 August 2008, for travel on or after 1 September 2008
If you are travelling with Sports Equipment, you will be eligible to check-in an extra 5kg of baggage allowance free of charge. This additional allowance is allocated above your purchased checked baggage allowance for Blue Saver or GO! Fares or above the inclusive checked baggage allowance for Velocity Gold and Silver Members or for Guests travelling on Flexible, Corporate Plus or Premium Economy fares.
Excess baggage charges will apply once the full allowance, including the additional 5kg allowance, has been exceeded.
If you are taking only sporting goods and you are travelling on a Blue Saver or GO! fare, you will still be required to purchase the checked baggage allowance of up to 23 kg. Remember you can pre-purchase this allowance for $8 per flight before you arrive at the airport otherwise you will be charged a $20 fee at the airport.
For example, if you have purchased a baggage allowance of 23kg, and are travelling with a bike, you will be eligible for a total checked baggage allowance of 28kg. If your bike weighs 10kg, you will be able to take additional checked baggage (such as a suitcase) weighing up to 18kg.
If you booked your flights before Aug 18th the old policy still applies.
So basically if you want to get it all on under the new policy your entire kits needs to be <28kg and then pack your carry on bag (clothes) to the density of lead and take that on board.
With all these sorts of things though it really does depend who you get at the check in desk on the day. In the past i've found Virgin pretty hassle free.